City planners probe downtown Philadelphia with 3D GIS

By GCN Staff

Jul 17, 2012

When city planners in Philadelphia wanted a better understanding of the building structure in City Center, the downtown hub of business, government, shopping and transportation, they turned to a New England company to provide facility management mapping services for a pilot project to test the effectiveness of a total 3D GIS solution.

Planners needed to know the relationships between pedestrian concourses, corridors, entrances and exits, air vents and emergency exits, and other aspects of the critical infrastructure, according to Arc News, a publication of Esri, a Redlands, Calif., a provider of GIS technology.

The robot went through each hall and room using LIDAR to measure the distance to each object by illuminating the target with light from a pulsating laser. Data points were collected illustrating where every object in the space was located including walls and doors.

The robot also took images with a camera that takes 360-degree pictures inside the building and then geo-references them, providing a continuous image of the space that can give a more accurate representation of the real buildings, the article explained.

The robotic platform collected thousands of data samples that were precisely geolocated to a point on a high-resolution map of the interior.

PenBay provided this data to the city in a building information system data model-compliant dataset that included CAD (AutoCAD) and 3D building information modeling (Revit) files of the area and a primary deliverable of an ArcGIS geodatabase.

A 3D video dataset was also collected for the entire captured area, which is of particular interest to public transit and the public safety community for planning and preparedness workflows.

The survey provided the city with a clear and accurate view of how its underground infrastructure links to its aboveground buildings and roads. Using ArcGIS for Server and the geodatabase, city planners have easy access to the data files over the Web, the article said.